1. Field of the Invention
The present invention relates to: an image forming apparatus such as copiers and printers; a method of acquiring toner-cartridge information from a toner cartridge removably mounted in such an image forming apparatus and equipped with a non-volatile memory; and a toner cartridge. Particularly, features of the invention reside in that the image forming apparatus permits the replacement of the toner cartridge without suspending an image forming operation of the image forming apparatus and in that confirmation of the mounted state of the toner cartridge, retrieval of information stored in the non-volatile memory of the mounted toner cartridge and such are accomplished easily.
2. Description of Related Art
The image forming apparatuses conventionally used, such as copiers and printers, include one in which a variety of cartridges containing various consumables, such as the toner cartridge containing therein a toner, are removably mounted in an apparatus main body.
In a case where the toner cartridge containing therein the toner is replaced, such an image forming apparatus requires a proper toner cartridge corresponding to an apparatus model or the like to be mounted therein in order to ensure proper image formation.
More recently, the following image forming apparatus has been proposed which employs a toner cartridge equipped with the non-volatile memory storing therein various information items including: cartridge-specific information such as an ID code; a color of the contained toner; toner quantity; use conditions; and the like. When this toner cartridge is mounted in the image forming apparatus, the image forming apparatus retrieves the information stored in the non-volatile memory so as to determine whether the mounted toner cartridge is proper or not (see Japanese Unexamined Patent Publications No.2002-169429 and No.2004-3309945).
The above image forming apparatus encounters the following problem when the toner cartridge is replaced. It is a common practice to temporarily suspend even an ongoing image forming operation before a front panel, a toner-cartridge mounting panel or the like is opened to replace the toner cartridge. The replacement of the toner cartridge involves the temporary suspension of the image forming operation, thus disabling a continuous image forming operation. Hence, image forming efficiency is lowered.
In order to form a full color image, the above image forming apparatuses is also adapted to permit a plurality of toner cartridges containing toners of different colors to be mounted in the apparatus main body.
In the image forming apparatus wherein the plural toner cartridges containing the toners of different colors are mounted, the apparatus main body is generally connected with the respective toner cartridges for discrete communication with the respective non-volatile memories thereof. Through such communications, the various information items stored in the respective non-volatile memories of the toner cartridges may be retrieved, or overwritten with new information.
However, problems of complicated wirings and control are encountered by the constitution wherein the apparatus main body is in discrete connection with the respective non-volatile memories of the toner cartridges for performing the discrete communication with the respective non-volatile memories of the toner cartridges.
An alternative constitution is also contemplated wherein the apparatus main body and the respective non-volatile memories of the toner cartridges are interconnected by means of one wire bus so that all the toner cartridges are sequentially accessed for data retrieval.
In this case, however, substantial time is taken to retrieve the data by sequentially accessing all the toner cartridges. More recently, the non-volatile memory of the toner cartridge, in particular, has been increased in capacity and hence, an enormous quantity of time is taken to retrieve the information stored in all the non-volatile memories of the toner cartridges.